This application is based upon and claims the benefit of Japanese Patent Applications No. 2002-65458 filed on Mar. 11, 2002, and No. 2003-27048 filed on Feb. 4, 2003, the content of which is incorporated herein by reference.
1. Field of the Invention
This invention relates to an air passage opening/closing device for opening and closing an air passage by moving a slide door including a flexible film member, and relates to a vehicle air conditioner using the air passage opening/closing device.
2. Description of the Related Art
An air passage opening/closing device for switching an air passage by movement of a film member is described in JP-A-8-2238. In this device, both ends of a film member are attached to a driving shaft and a driven shaft (following shaft) rotatably mounted in an air-conditioning case, and the film member is moved by using a winding mechanism of the driving and driven shafts. Therefore, the driving and driven shafts are required to be operatively linked with each other, and an interlock mechanism such as a pulley and a wire is required. As a result, the number of components of the device is increased, and its assemble process is complicated, thereby increasing its production cost.
However, when the winding mechanism is simply not provided, and a moving end of the film member is made free, it is difficult to prevent an air leakage. Further, in this case, deformation of the film member is readily caused due to bending habit of the free end or the gravity of the film member.
It is an object of the present invention to prevent air leakage due to a bending habit or gravity of a flexible film member, in an air passage opening/closing device for opening and closing an opening portion of an air passage, using a slide door including the flexible film member.
According to the present invention, an air passage opening/closing device includes a case for defining an opening portion of an air passage through which air flows, a slide door disposed in the case to be movable in a door moving direction for opening and closing the opening portion, a driving device for moving the slide door, a guide member provided in the case for defining a guide ditch for guiding a movement of a flexible film member, and a pushing member that pushes the film member toward a seal surface around the opening portion of the case. The flexible film member is disposed at an upstream side of the opening portion in an air flow direction, and the film member has a free top end in the door moving direction. Further, the free top end of the film member is moved forward along the guide ditch by a pushing force from the driving device to the film member. On the other hand, the seal surface of the case has a first surface in a direction parallel to the door moving direction, and a second surface in a direction perpendicular to the door moving direction. In the air passage opening/closing device, the pushing member is disposed to push the film member toward the second surface such that a clearance between the film member and the second surface becomes smaller than a clearance between the film member and first surface. Accordingly, even when the film member is deformed due to a bending habit and gravity, because the film member is pushed by the pushing member to the second surface in the seal surface, the film member can be forcibly approached to the second surface in the seal surface of a peripheral portion of the opening portion. Therefore, air leakage caused by the deformation of the film member due to the bending habit and the gravity of the film member can be effectively restricted.
Preferably, the pushing member is disposed in the slide door partially at least in a center area of the slide door in the direction perpendicular to the door moving direction. In this case, it can restrict a sliding area between the pushing member and the film member from being increased, while a clearance between the film member and the second surface can be reduced in the center area in the direction perpendicular to the door moving direction. Therefore, door operation force for operating the slide door can be reduced, and the air leakage can be effectively restricted. However, the pushing member can be disposed in the slide door in an entire length of the slide door in the direction perpendicular to the door moving direction. In this case, the film member can be approached to the seal surface along the entire length in the direction perpendicular to the door moving direction, and the air leakage can be further restricted.
In the present invention, the pushing member can be provided integrally with the guiding member. In this case, the pushing member can be provided in the guide member to be offset from a wall surface of the guide member toward the second surface in the seal surface, at a portion around the second surface. Alternatively, the pushing member can be disposed on a wall surface of the guide member defining the guide ditch, to reduce partially a ditch dimension in an area around the second surface. Even in this case, the air leakage can be effectively restricted.
Further, in the present invention, the guide ditch is provided such that the clearance between the film member and the second surface of the case is made smaller than the clearance between the film member and the first surface of the case, without providing the special pushing member. Even in this case, the air leakage caused by the deformation of film member due to the being habit and the gravity of the film member can be effectively restricted.
The air passage opening/closing device of the present invention can be suitably used for a vehicle air conditioner. For example, the slide door can be used as an air mixing door that adjusts a flow ratio between an air amount passing through a heater core and an air amount passing through a bypass passage while bypassing the heater core in the case. Alternatively, the slide door can be used as an air outlet mode-switching door for switching an air outlet mode such as a face mode, a foot mode, a foot-defroster mode and a defroster mode, in a vehicle air conditioner.